Dental matrix-clamp



No. 625,888. Patented may 30., I889.

L. P. 'LEONARD.

v DENTAL MATR'I'X CLAMP.

(Application filed Feb. 9, 1898.)

4N0 Model.)

NITED STAT-ES PATENT ()FFICE.

LAURENCE P. LEONARD, OF WASECA, MINNESOTA.

DENTAL MATRlX-CLAM P.

SPECIFICATION forming part of Letters jPatent No. 625,888, dated May 30,1899/ Application filed February 9, 1898. Serial No. 669,665. (Nomodel.) I

To (ZZZ whom it may concern:

Be it known that I, LAURENCE P. LEONARD, a citizen of the United States,residing at Waseca, in the county of Waseca and State of Minnesota,haveinvented certain new and usefulImprovements in Dental Matrix-Clamps; andI do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

My invention relates to an improvement in dental matrix-clamps employedby dentists to hold the matrix in place While filling approximalcavities in the teeth, and has for its object to provide a olampwhioh isaccurate and complete in function, simple and inexpensive inconstruction, and easy to manipulate.

My invention consists in a clamp having a double-spring clampingarm, oneof the springs of which is adapted to reinforce the action of the other,and jaws secured between the ends of said springs having wide shoulderswhich fit the rotundity of the teeth and overlapping doublewedge-shapedpoints; and it also further consists in the construction, combination,and arrangement of the several parts, as more fully hereinafterdescribed and specifically claimed.

Referring to the drawings, Figure l is a top plan View of the clampapplied to a tooth ready for use; Fig. 2, a similar View showing theclamp applied to a tooth opposite to that shown in Fig. 1; Fig. 3, afront view in elevation of the clamp; Fig. 4, a side view of two teeth,showing the V or wedge shaped interproximal space above the line mo ofthe gum; Fig. 5, a plan View of same; Fig. 6, a cross-section of one ofthe double wedgeshaped points which is adapted to fit into theinterproximal space; Fig. 7, a detail of the two double wedge-shapedpoints of the clamp; Fig. 8, a plan View of modification of the clamp asit is constructed when used as a rubber-dam'clamp; Fig. 9, a detail viewshowing the spring clamping-arm pivoted so as to turn on the jaws.

Cavities are now cut wider and larger by the dental profession than theyused to be, (see dotted lines, Fig. 2, showing old manner of cutting acavity,) making it necessary to have lateral support to thematrix-strip. (See Figs. 1 and 2.) Fillings are also better contoured,makin git necessary to have the wedge between the teeth very thin nearthe adjacent surfaces of the teeth, so that the matrix and filling canbe forced well against the approXimal tooth, thus preserving the naturalshape of the tooth and the interproximal space between the teeth. Hencethe advantage of wedge-shaped interproximal space or cavity B is formed,the base or larger portion of which is toward the gum and the point to-Ward the crown 'or grinding-surface of the teeth.

B represents the clamping-arm, composed of two semicircular springs C D,overlapping or situated one within the other, which together constitutea double-spring clampingarm; C D, the free ends of said springs,respectively; E, clamping jaws secured between the ends C D of thesprings by soldering or rivet-ing, or, if desired, they may be pivoted,as shown in Fig. 9, so as to turn; F, double wedge -shaped points on theinner ends of said clamping-jaws adapted to overlap and their sides towedge against each other by the action of the spring clampingarms, bywhich means the matrix strip or plate will be pressed tightly againstthe center of the cavity in the tooth; G G, shoulders on the jaws E,situated about midway the length of the same, adapted to press thematrix strip or plate against the outside of the tooth on each side ofthe cavity therein. The double wedge-shaped points of the clampingjawsare approximately straight on one: side, while their opposite sides areconcaved, as at E, to lit the general contour of the tooth and also theVor wedge shaped interproximal space or cavity, and thereby give abetter contact or clamping surface, first, on the center of the cavity,where the points pass each other; second, at the walls or edges of thecavity, and, third, on the lateral surfaces of the tooth, where theshoulders G G hold the matrix doubly secure while the filling is beingpacked into place.

Itwill readilybe seen that by constructing the clamping-arm, as hereindescribed,of thin double overlapping springs ,a far greater amount ofstrength and elasticity is obtained than would be the case with a singlespring of the same amount of metal, and that as the clamping-jaws areattached to the ends of this spring-arm their ran geof action is greatlyfacilitated.

By means of the pivoted clamping-arm shown in Fig. 9 the matrix-clampcan be adjusted to fit a front or posterior cavity by simply rotatingthe clamping-arm on the pivot and inverting the same, thus keeping theclamping-arm toward the back of the mouth and out of the way of theoperator, or the matrix-clamp can be made all in one piece without ajoint, having one for each class of these cavities.

In applying the device to the cavity of the tooth the matrix strip orplate is bent to the shape of the tooth and is inserted between thedecayed tooth and the one adjacent therebeing pivoted, as at H E, Fig.7, to allow better adaptation of the parts F F and G G to the teeth inirregular positions.

Having thus described my invention, what I claim is 1. A dental matrixclamp comprising a spring clamping-arm, and jaws carried by the endsthereof provided with wedge-shaped overlapping points,substantially asdescribed.-

2. A dental matrix-clamp comprising a spring clam ping-arm, a pair ofclam ping-j aws provided with shoulders and double wedge= shapedoverlapping points, one of the sides of said points being approximatelystraight and the opposite side concaved, substantially as described.

3. A dental matrix clam-p comprising a pair of clamping jaws withoverlapping wed ge-shaped points,and a clamping-arm pivoted to said jawsadapted to turn longitudi= nally of the teeth, substantially asdescribed.

4. A dental clamp comprising clampingjaws, and a spring clamping-arm,adapted to turn longitudinally of the teeth, substantially as described.

In testimony whereof I aflix my signature in presence of two witnesses.

LAURENCE P. LEONARD.

Witnesses:

JOHN T. HECH, FRANK MCLIN.

